Question
Mon April 16, 2012 By:

in one of the videos on heating effect of electric current an experiment was shown in which nichrome and aluminium wires were connected in a circuit and nichrome wire became red hot and when it was removed and only aluminium wire was kept after some time it became red hot also then why the wires used for electrical transmission made of aluminium doesnot melt after some time as heat is produced here also in this case??

Expert Reply
Tue April 17, 2012
Aluminum conductors cabled around a steel support wire are commonly used for large high voltage transmission lines because aluminum is much less expensive than copper. The steel support wire is needed because aluminum has relatively low tensile strength. Low voltage household, office, and factory electric wires are usually copper, which does not have the corrosion problems common to aluminum wires.
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